Refilling and servicing Armstrong Lever Arm rear shocks

[fishyboy]

Hi all,
While cleaning up the rear suspension on my 1961 BT7 after a 30 year wait (http://www.britishcarforum.com/bcf/...ip-I-decided-to-clean-my-1961-Healey-3000-BT7) I took the opportunity to check the level on the rear Armstrong shocks (not having done so in 30 years). The shocks have always passed the "bounce test" (bouncing each corner) and appear to be working fine, but at least I expected the fluid to be severely depleted (I read somewhere they a supposed to leak a little in order to lubricate the arm). I was amazed to find the shocks were fully topped up. However, I drew of some liquid and it was quite dark with what looked like disintegrated rubber causing the colour.

I was wondering if it was easy to service these shocks (this guy make it look pretty straight forward - https://www.youtube.com/watch?v=oGUhb90Voyk) amusing they are easy to remove. On the other hand should I leave well alone, apart form sucking out the old fluid and replacing with some fresh shock oil.

What do you all think?

Phil

 

[John Turney]

R&R the rear shocks on a BT7 are a bit more difficult than the TR6 because of the way the link is arranged. Changing the fluid in the shock itself will be the same. You will have to take apart the top and the bottom to get all the old fluid out. When you pull the valve out of the bottom, inspect the O-rings. If the shock hasn't leaked, those O-rings may be the source the disintegrating rubber. I've been able to find a wide selection of O-rings at my local Ace Hardware, but YMMD. [Edit: I just realized from your other post that you're in the UK. You probably don't have a local Ace Hardware.]

Pay attention to woking the lever to get all the air out when refilling, and have the car supported by the rear axle rather than the frame when reinstalling the shocks so the link bushings are tightened in the normal ride height.

Oh, and clean the outside of the shock before opening up so you don't get dirt inside.

 

[fishyboy]

Thanks John
By "supported by the rear axle" do I put my trolley jack under the rear axle?
Phil

 

[John Turney]

Put jackstands under the rear axle. NEVER work under the car with it just supported by a jack. Please excuse me if that's not what you meant.

I put my trolly jack under the differential until it's high enough to put jackstands under each side of the axle.

 

[roscoe]

Do take care to keep dirt out of these units as that is what can cause several problems. When you fill them you should exercise the lever arm to work any air out of the system. When serviced, the lever should offer smooth, moderate resistance from full up to full down and reverse.